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My research interests lie in the study of evolution, with a special interest in evolutionary genetics. I am interested in the application of appropriate molecular markers to study both past and present population processes and to investigate the causes of phenotypic patterns.
During my MSc thesis at the Anthropological Institute and Museum of the University of Zurich, Switzerland, I developed male-specific markers for orangutans and applied them to wild orangutan (Pongo spp.) samples from the whole distribution range of the genus to investigate dispersal and phylogeny. Polymorphic Y-specific markers are lacking for most species and had not yet been applied to orangutans. I cross-amplified human-derived microsatellite markers and subsequently designed orangutan-specific primers. Four Y-chromosomal SNPs were previously known and additional ones identified through sequencing of microsatellite flanking regions. I modified published SNP typing methods so that only one labeled primer was required and the SNP typing could be performed together with the microsatellite typing. I established two multiplex PCRs to amplify 11 microsatellites, 6 SNPs, and 1 insertion-deletion polymorphism from low-quality fecal samples. 173 male orangutans from the whole range of the two orangutan species (Bornean orangutan Pongo pygmaeus, Sumatran orangutan Pongo abelii) were screened. For nine populations, mitochondrial HVRI sequence data was also analyzed.
Many of the microsatellite markers were polymorphic within populations, allowing comparisons of Y-chromosomal and mitochondrial variation at a population level. Most of the genetic variation of Y chromosomes was contained within populations, whereas most of the mitochondrial variation was found between populations. Median-joining networks showed grouping of haplotypes according to geographic origin only for mitochondrial but not for Y-chromosomal haplotypes. These findings support the hypothesis derived from behavioral observations that dispersal is male-biased in orangutans (i.e. males either disperse further, more frequently, or both). Median-joining networks illustrated the clear genetic separation of Bornean and Sumatran orangutans. Bayesian analyses (BATWING) were performed to estimate the coalescent date of extant orangutan Y chromosomes and infer parameters related to past population growth. With a time to the most recent common ancestor of all orangutan Y chromosomes of around 60,000 years, this estimate was about fifty-fold lower than corresponding estimates for mitochondria. It suggests that there was rather recent gene flow between the two islands of Borneo and Sumatra during one of the periodical exposures of the Sunda shelf. Y-chromosomal variation within the 50,000 Bornean orangutans was higher than within the 6500 Sumatran orangutans, whereas the opposite pattern was previously found for mitochondrial and X-chromosomal genetic variation. Higher genetic diversity within the smaller population on Sumatra had been explained by Sumatran orangutans possibly being made up of several relict populations having retreated to northern Sumatra from their ancient distribution across south-eastern Asia. This high diversity would then have been lost from the Sumatran Y chromosomes either through genetic drift or through a selective sweep acting on the Y chromosome.
Since 2010: PhD student at the Institute of Evolutionary Biology and Environmental Studies at the University of Zurich, Switzerland, working on the evolutionary genetics of isolated populations
2008-2010: Master of Science in Biology, Anthropology at the University of Zurich, Switzerland
2004-2007: Bachelor of Science in Biology at the University of Zurich, Switzerland, and the University College Dublin, Ireland (exchange semester in 2007)
2010: MSc thesis: “Male-specific markers in orangutans (Pongo spp.): dispersal and phylogeny”
2002: Matura thesis: „Untersuchungen zur Biologie des Alpenseglers Tachymarptis melba – Bettelverhalten, Geruchsempfindlichkeit, Nestwechsel und Lage der Nester“
